1. Field of the Invention
The invention relates to a method and a device for determining the frequency distribution of the signal levels of a measured signal measured respectively in overlapping observation intervals.
2. Discussion of the Background
A device for recording and storing a measured signal is known, for example, from DE 10 2004 019 967 A1.
Cyclical measurements of signals in the time or frequency domain are implemented either in overlapping observation intervals or in non-overlapping observation intervals. By comparison with a measurement in overlapping observation intervals, a measurement in non-overlapping observation intervals provides a comparatively-low correlation, which leads to significant fluctuations in the signal levels of the measured signal measured in a time or frequency raster between the individual observation intervals. These fluctuations in the signal level of the measured signal over the individual observation intervals disadvantageously present the user with an unsettled display of the measured signal on the screen of the display device.
In order to avoid this kind of jitter effect in measurement technology, overlapping observation intervals are preferred, wherein each observation interval consists of an identical total number NofFrames of measurement cycles, as shown in FIG. 1, and wherein, in each case, two successive observation intervals are delayed relative to one another by a relatively-smaller number NofFramesNextCalc of measurement cycles. Since the number NofFramesNextCalc of measurement cycles between two observation intervals delayed relative to one another is significantly smaller than the total number NofFrames of measurement cycles in every observation interval, the evaluation of measured data is quasi-parallel or respectively quasi-smooth. Accordingly, a plurality of observation intervals—NofFrames/NofFramesNextCalc observation intervals—must be detected and evaluated in parallel, which is difficult to realize in real time even with currently-available computer performance.